Trouble using movefile to change filenames

I have a code designed to rename a folder full of files by changing the numbers to 4 digits. for example a file text_#1.txt would be changed to text_#0001.txt. It is working perfectly unless the number is already four digits long in which case this error appears:

Error using movefile Cannot copy or move a file or directory onto itself.

Here is the script I am using:

for k = 1:numel(j)

    name = j(k).name;   %store the names in a variable
    nums = regexp(name,'\d*','match');   %store individual name in variable
    oldstr = cell2mat(nums(end));    %the old string as a number
    newstr = num2str(sprintf('%04d',str2num(cell2mat(nums(end)))));   %the new string as a number
    old = fullfile(folder,name);    %the old file
    new = strrep(fullfile(folder,name),sprintf('#%s',oldstr),sprintf('#%s',newstr));   %the new filename
    comp = strcmp(oldstr,newstr);
    if comp == 0
        movefile(old,new)    %change the filenames
    else
        continue
    end
end

it does not work when it reaches a file such as text_#1000. because this already has 4 digits the old and new filenames are identical and matlab returns the above error.

I want it to skip the file if it is already in the correct format but the same error message keeps appearing. I also tried using a try, catch loop instead of if,else. If anyone can help it would be much appreciated.

[Image Analyst]

Give the filename strings for the case where it does NOT work.

[Will]

i made an edit

[dpb]

Superficially, logic looks ok...I might rewrite the conditional as

if ~comp
  movefile(old,new)    %change the filenames
end

since the 'continue' is superfluous given it's placement in the loop, but that's really immaterial.

Use the debugger and step thru with one of the failing name patterns and see where the logic actual goes wrong...

[Will]

turns out it works either way. i got so caught up in the script i had matlab in the wrong folder. thanks anyway

Answer 1

[Star Strider]

I would use exist instead of ‘comp == 0’, something like:

    if ~exist(newstr,'file')
        movefile(old,new)    %change the filenames
    else
        continue
    end

No promises because I can’t test your code, but first testing to see if the file already exists would prevent the error.

[Will]

turns out it works either way. i got so caught up in the script i had matlab in the wrong folder. thanks anyway

[Star Strider]

My pleasure!